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61.
Interobserver variation in the interpretation of abdominal radiographs   总被引:2,自引:0,他引:2  
A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern.  相似文献   
62.
Effect of intersection spacing on MR image contrast and study time   总被引:1,自引:0,他引:1  
Kneeland  JB; Shimakawa  A; Wehrli  FW 《Radiology》1986,158(3):819-822
The effects of section separation on image contrast and calculated T1 relaxation times were investigated in healthy volunteers and a phantom using an early commercial version magnetic resonance imaging system. The effects are explained qualitatively on the basis of side lobes of excitation occurring outside the selected section resulting in reduction of the time permitted for T1 relaxation. The options for dealing with imperfect section selection, including separation of the sections (i.e., leaving gaps) and nonsequential excitation, are illustrated and the trade-offs involved in each explained.  相似文献   
63.
64.
Kim  D; Porter  DH; Siegel  JB; Simon  M 《Radiology》1989,172(3):721-723
Various complications have been reported after insertion of the Greenfield filter. This report describes an unusual complication after suprarenal placement of this filter: spreading of the filter struts, with perforation of the inferior vena cava, and penetration of the aorta and a vertebral body, followed by fracture of one of the struts.  相似文献   
65.
A retrospective study was made of all patients aged over 65 years with hypothermia discharged from or dying in the Victoria Infirmary, Glasgow in the years 1977-81. Full follow-up data were obtained on 81 of the 91 patients identified. Patients were divided into cases of primary and secondary hypothermia. There were no significant differences between the two groups in initial mortality mean age on admission or mean temperature on admission, but there was a highly significant (P less than 0.001) difference in long-term outcome: the 3-year mortality in patients who survived the index admission was 100% in the primary group and 24% in the secondary group.  相似文献   
66.
67.
High-resolution MR imaging with local coils   总被引:4,自引:0,他引:4  
Kneeland  JB; Hyde  JS 《Radiology》1989,171(1):1-7
We propose the following rules to govern the choice of local coils by the practicing radiologist: 1. Smaller coils permit smaller FOVs and better resolution. The coil should be as small as possible. 2. Match the ROS of the coil to the FOV, which will be determined by the anatomic region of interest. 3. For the case of a choice between surface coils or between a surface and a whole- or partial-volume coil, the anatomic region should lie on the high side of the crossover point. For the case of a choice among whole-volume coils, the smallest coil that surrounds the region of interest should be chosen. 4. Considerations in regard to the anatomic shape or the need to vary the position of the structure may alter the choice of coil from that obtained by S/N considerations alone.  相似文献   
68.
Kirkpatrick  JB; Hayman  LA 《Radiology》1987,162(2):509-511
Patchy white-matter lesions occur in the magnetic resonance (MR) imaging brain studies of 20%-30% of neurologically healthy elderly subjects. To determine the frequency of histologically verifiable white-matter lesions at autopsy in such subjects the authors examined serial, microscopic, whole brain sections from 15 clinically healthy subjects aged 52-72 years. Small white-matter lesions were found in 12. In these 12, zones of atrophic perivascular demyelination were present in eight brains. These are not the familiar thrombotic, embolic, or ischemic vascular lesions that produce acute necrosis. This mild vascular insufficiency produces atrophy, which has been recognized in the pathology literature but whose clinical significance remains unknown. Other lesions seen were small vascular malformations in the centrum ovale in four brains, diverticula of the lateral ventricle extending into the white matter in three, and an isolated central white-matter infarction in one. All of these lesions are probably the basis of the patchy white-matter lesions seen on MR imaging studies in the neurologically healthy elderly population.  相似文献   
69.
70.
蛋白质组学及其相关技术在运动人体科学中的应用   总被引:1,自引:0,他引:1  
目的:对蛋白组学及蛋白芯片技术发展现状进行综述,为该技术在运动医学中的应用提供参考资料。资料来源:应用计算机检索PubMed2003-01/2006-12期间相关蛋白组学及蛋白芯片技术方面的文章,检索词“exercise AND protein chip,protein microarray”,并限定文章语言种类为English。同时计算机检索万方数据库2003-01/2006-12期间相关蛋白组学及蛋白芯片技术方面的文章,检索词“蛋白质,运动锻炼,运动医学”,并限定文章语言种类为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。纳入标准:文章所述内容应与蛋白质组学及蛋白质芯片技术的研究相关。排除标准:重复研究或Meta分析类文章。资料提炼:共收集到312篇相关文献,32篇文献符合纳入标准,排除的280篇文献为内容陈旧或重复。资料综合:蛋白组学研究已成为基因组学研究后生命科学发展的大方向之一。它研究的主要内容包括:蛋白质分离与鉴定、蛋白质功能的确定、蛋白质翻译后修饰及相互作用、各种疾病或疲劳标志物的筛选与疾病诊断、生物信息学及药物开发等方面。文章在对蛋白质组学的发展及其相关技术在运动人体科学中的应用现状进行综述的基础上,对运动人体科学未来的发展方向进行了展望。由于蛋白质组学的建立以及蛋白质芯片技术的逐步完善,对运动人体科学的研究及其发展将起到很好的促进作用。结论:未来将从分子水平上阐明运动与人体适应的分子生物学机制,研究热点将集中于从运动营养蛋白质组学、反兴奋剂的蛋白质芯片技术、运动员机能评定的蛋白质芯片研究等方面。  相似文献   
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